S-(Alpha, Alpha&#39;-Disubstituted-Alpha&#34;-Acetic Acid) Substituted Dithiocarbonate Derivatives for Controlled Radical Polymerizations, Process and Polymers Made Therefrom

ABSTRACT

Dithiocarbonate derivatives are disclosed, along with a process for preparing the same. The dithiocarbonate compounds can be utilized as initators, chain transfer agents and/or terminators in controlled free radical polymerizations. The dithiocarbonates can be used to produce polymers having narrow molecular weight distribution. Advantageously, the compounds of the present invention can also introduce functional groups into the resulting polymers. The dithiocarbonate compounds have low odor and are substantially colorless.

CROSS REFERENCE

This patent application is a continuation-in-part application based onU.S. application Ser. No. 09/505,749 filed Feb. 16, 2000 forS,S′-Bis-(α, α′-Disubstituted-α″-Acetic Acid)-Trithiocarbonates AndDerivatives As Initiator—Chain Transfer Agent—Terminator For ControlledRadical Polymerizations And The Process For Making The Same.

FIELD OF THE INVENTION

The present invention relates to s,s′-bis-(α, α′-disubstituted-α″-aceticacid)-trithiocarbonates and derivatives thereof, as well as a processfor making the same. Moreover, other functional end groups can bederived from the carboxylic acid end groups. The compounds can beutilized as initiators, chain transfer agents, or terminators forcontrolled free radical polymerizations. Free radical polymerizationsutilizing s,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonatecompounds generally form telechelic polymers. If an initiator other thanthe s,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonatecompound is also utilized, a polymer having a single functional endgroup is formed in proportion to the amount of the initiator to thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundutilized.

In a further embodiment, dithiocarbonate derivatives are disclosed,along with a process for preparing the same. The dithiocarbonatecompounds can be utilized as initators, chain transfer agents and/orterminators in controlled free radical polymerizations. Thedithiocarbonates can be used to produce polymers having narrow molecularweight distribution. Advantageously, the compounds of the presentinvention can also introduce functional groups into the resultingpolymers. The dithiocarbonate compounds have low odor and aresubstantially colorless.

BACKGROUND OF THE INVENTION

Although several members of the class of organic thiocarbonates havebeen known for many years and various routes have been employed fortheir synthesis, the s,s′-bis-(α,α′-disubstituted-α″-aceticacid)-trithiocarbonate compounds of the present invention have not beendisclosed. Trithiocarbonate compounds have been claimed for variousapplications, such as pesticides for agriculture, and also aslubricating oil additives.

Traditional methods of producing block copolymers, such as by livingpolymerization or the linking of end functional polymers, suffer manydisadvantages, such as the restricted type monomers which can beutilized, low conversion rates, strict requirements on reactionconditions, and monomer purity. Difficulties associated with end linkingmethods include conducting reactions between polymers, and problems ofproducing a desired pure end functional polymer. Thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundsof the present invention can alleviate the above noted problems anddifficulties when utilized in free radical polymerizations.

The prior art WO98/01478 reference discloses the use of thiocarbonatesto conduct living free radical polymerizations. The reference is limitedto alkyl and benzyl functional groups, and is unable to make any aryl orcarboxylic acid substituted trithiocarbonates with general methods knownto the art. Synthesis, p 894 (1986), J. Chemical Research (Synopsis), p478 (1995), and Synthetic Communications, Vol. 18, p 1531 (1988). Wehave also found the conversion for the dibenzyl derivatives disclosed intheir example 26 to be very slow compared to the present invention whenpolymerizing acrylate, as can be seen in the Example section of thisapplication. The WO/01478 reference states in the background thatexperiments have shown that dithiocarbamate derivatives have lowtransfer constants and are substantially ineffective in conferringliving characteristics to radical polymerizations.

Macromolecules, 32, p 6977-6980 (1999) states that

dithiocarbamate compounds:

cannot control polymerization and are not effective RAFT agents.Additionally, carboxyl end groups cannot be formed utilizing theprocesses disclosed. Also WO 99/35177 and Macromolecules, RapidCommunications, 21, p 1035-1039 (2001) finds that R, R¹, and R² need tobe fine tuned to control polymerization, meaning there is no guaranteeall dialkyl dithiocarbamate will work as RAFT agents. Moreover, thesubstituent of the single bonded sulfur atom cannot be a carboxylic acidcontaining group in their synthesis.

U.S. Pat. No. 6,153,705 relates to a process for polymerizing blockpolymers of general formula (I):

in which process the following are brought into contact with each other:

an ethylenically unsaturated monomer of formula:CYY′(═CW⁻CW′)_(a)═CH₂,

-   -   a precursor compound of general formula (II):    -   and a radical polymerization initiator.

Macromolecule Rapid Communications 2001, 22, p 1497-1503 and U.S. Pat.No. 6,153,705 disclose various xanthate compounds. The references cannotprepare the xanthate compounds of the present invention utilizing themethods disclosed within the references. 1) Alkylation with tertiaryalkyl halides disclosed in the '705 patent will result in elimination,not substitution. The α-halo-α′, α″-dialkylacetic acid disclosed by thereference cannot be alkylated. 2) The compounds of the present inventioncontain a tertiary carbon attached to the single bonded sulfur atom ofthe compound. The '705 patent preferably utilizes an R¹ group having asecondary carbon atom which results in a lower chain transfercoefficient than the present invention. Moreover, the xanthatesdisclosed by the references have been found to be less effective.

Unexpectedly, in view of the prior art, the compounds of the presentinvention are able to confer living characteristics to a free radicalpolymerization.

SUMMARY OF THE INVENTION

The present invention relates to s,s′-bis-(α,α′-disubstituted-α″-aceticacid)-trithiocarbonates which have the general formula:

where R¹ and R² are set forth below, to derivatives thereof, and to aprocess for making the same.

The s,s′-bis-(α,α′-disubstituted-α″-acetic acid) trithiocarbonatecompounds can generally be formed from carbon disulfide, a haloform, anda ketone in a strong base, such as sodium hydroxide, followed byacidification. The s,s′-bis-(α,α′-disubstituted-α″-acetic acid)trithiocarbonate compounds can be used as inifertors, i.e. as initiatorsand chain transfer agents, and/or chain terminators or as achain-transfer agent during polymerization. The compounds can thus beutilized to control free radical polymerization thermally and chemicallyto give narrow molecular weight distributions. Polymerization ofmonomers can be in bulk, in emulsion, or in solution. Block copolymerscan be made if two or more monomers are polymerized in succession. Thedifunctional acid end groups present can further react with otherreactive polymers or monomers to form block or random copolymers. Freeradical polymerizations utilizing thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundsgenerally form telechelic polymers. If an initiator other than thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundis also utilized, a polymer having a single functional end group isformed in proportion to the amount of said other initiator to thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundutilized.

In a further embodiment, dithiocarbonate compounds of the presentinvention have the general formula:

wherein D, R¹², R¹³ and j are defined hereinbelow. Preferably, thesubstituent D is an alkoxy or an amine derivative, preferably adialkylamino derivative, and thus, the dithiocarbonate compounds arexanthate and dithiocarbamate derivatives. A process for preparing thedithiocarbonate compounds is disclosed.

The dithiocarbonate compounds can be utilized as chain transfer agentsin free radical polymerizations, as well as initiators and/or chainterminators. Narrow molecular weight distribution polymers canadvantageously be produced with the dithiocarbonates of the presentinvention. The polymers formed in the presence of the dithiocarbonatecompounds have at least one terminal carboxyl group which can be furtherreacted to form block or random copolymers. The monomers or polymerspolymerized onto the dithiocarbonate compounds are added between thesingle bonded sulfur atom and the adjacent tertiary carbon atom. Thepolymerizations are conducted under inert atmospheres. The compoundsand/or the polymers or copolymers of the present invention can be madewater soluble or water dispersible through their metal or ammonium saltsof the carboxylic acid group.

Accordingly, polymers having the following formula can be producedutilizing the dithiocarbonate compounds of the present invention:

wherein, D, R¹², R¹³, polymer, j and n are defined hereinbelow.

DETAILED DESCRIPTION OF THE INVENTION

The s,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate andderivatives prepared by the processes disclosed later herein generallycan be described by the formula:

wherein R¹ and R², independently, can be the same or different, and canbe linear or branched alkyls having from 1 to about 6 carbon atoms, or aC₁ to about C₆ alkyl having one or more substituents, or one or morearyls or a substituted aryl group having 1 to 6 substituents on the arylring, where the one or more substituents, independently, comprise anallyl having from 1 to 6 carbon atoms; or an aryl; or a halogen such asfluorine or chlorine; or a cyano group; or an ether having a total offrom 2 to about 20 carbon atoms such as methoxy, or hexanoxy; or anitro; or combinations thereof. Examples of such compounds includes,s′-bis-2-methyl-2-propanoic acid-trithiocarbonate ands,s′-bis-(2-phenyl-2-propanoic acid)-trithiocarbonate. R¹ and R² canalso form or be a part of a cyclic ring having from 5 to about 12 totalcarbon atoms. R¹ and R² are preferably, independently, methyl or phenylgroups.

The abbreviated reaction formula for thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonates of thepresent invention can be generally written as follows:

The process utilized to form the s,s′-bis-(α,α′-disubstituted-α″-aceticacid)-trithiocarbonate compounds of the present invention is generally amulti-step process and includes combining the carbon disulfide and abase whereby an intermediate trithio structure is formed, see I, II,III, and IV. Ketone can serve as solvent for the carbon disulfide/basereaction and thus can be added in the first step of the reaction. In thesecond step of the reaction, the haloform, or haloform and ketone, or aα-trihalomethyl-α-alkanol are added to the trithio intermediate mixtureand reacted in the presence of additional base, see V, VI, and VII. Theformed reaction product, see IX, is subsequently acidified, thuscompleting the reaction and forming the above describeds,s′-bis-(α,α′-disubstituted-α″-acetic acid) trithiocarbonate compound,see X.

The reaction is carried out at a temperature sufficient to complete theinteraction of the reactants so as to produce thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundin a desired time. The reaction can be carried out at any temperaturewithin a wide range from about the freezing point of the reaction massto about the reflux temperature of the solvent. The reaction temperatureis generally from about minus 15° C. to about 80° C., desirably fromabout 0° C. to about 50° C., and preferably from about 15° C. to about35° C., with room temperature being preferred. The reaction can beperformed at atmospheric pressure. The reaction time depends uponseveral factors, with the temperature being most influential. Thereaction is generally complete within 20 hours and preferably within 10hours.

A phase transfer catalyst is preferably utilized if a solvent is used inthe reaction. Examples of solvents are set forth herein below. Theketone utilized in the reaction may double as a solvent, and thereforeno catalyst usually is needed. The amount of phase transfer catalyst,when utilized in the present invention, is generally from about 0.1 molepercent to about 10 mole percent, desirably from about 0.5 mole percentto about 5 mole percent and preferably from about 2 mole percent toabout 4 mole percent per mole of carbon disulfide. The phase transfercatalysts can be polyether, and/or an onium salt including a quaternaryor tertiary organic compound of a group VA or VIA element of thePeriodic Table and salts thereof. Most preferred are quaternary amines,and salts thereof.

“Onium salts” more particularly refer to tertiary or quaternary aminesand salts such as are generally used in the phase transfer catalysis ofheterogeneous reaction in immiscible liquids. The general requirementfor the onium salt chosen is that it be soluble in both the organic andaqueous phases, when these two liquid phases are present, and usually alittle more soluble in the organic phase than the aqueous phase. Thereaction will also proceed with a phase transfer catalyst when there isonly a single organic liquid phase present, but such a reaction is lesspreferable than one in which both aqueous and organic liquid phases arepresent. A wide variety of onium salts is effective in this ketoformsynthesis.

The onium salts include the well-known salts, tertiary amines andquaternary compounds of group VA elements of the Periodic Table, andsome Group VIA elements such as are disclosed in the U.S. Pat. No.3,992,432 and in a review in Angewandte Chemie, International Edition inEnglish, 16 493-558 (August 1977). Discussed therein are various aniontransfer reactions where the phase transfer catalyst exchanges itsoriginal ion for other ions in the aqueous phase, making it possible tocarry our chemistry there with the transported anion, including OH-ions.

The onium salts used in this synthesis include one or more groups havingthe formula (R_(n)Y)⁺X⁻, wherein Y is either a pentavalent ion derivedfrom an element of Group VA, or a tetravalent ion derived from anelement of Group VIA; R is an organic moiety of the salt molecule bondedto Y by four covalent linkages when Y is pentavalent, and three covalentlinkages when Y is tetravalent; X⁻ is an anion which will dissociatefrom the cation (R_(n)Y)⁺ in an aqueous environment. The group (R_(n)Y)⁺X⁻ may be repeated as in the case of dibasic quaternary salts having twopentavalent Group VA ions substituted in the manner described.

The preferred onium salts for use in the invention have the formula(R^(A)R^(B)R^(C)R^(D)Y⁺)X⁻wherein Y is N or P, and R^(A)-R^(D) are monovalent hydrocarbon radicalspreferably selected from the group consisting of alkyl, alkenyl, aryl,alkaryl, aralkyl, and cycloalkyl moieties or radicals, optionallysubstituted with suitable heteroatom-containing functional groups. Theonium salts are generally selected to be less preferentially lesssoluble in the less polar of the two distinct liquid phases. Any of thesalts disclosed in the U.S. Pat. No. 3,992,432 will be found effective,but most preferred are those in which the total number of carbon atomsin R^(A), R^(B), R^(C), and R^(D) cumulatively range from about 13 toabout 57, and preferably range from about 16 to about 30. Most preferredonium salts have Y═N, and hydrocarbon radicals where R^(A) is CH₃, andR^(B), R^(C), and R^(D) are each selected from the group consisting ofn-C₂H₅, n-C₄H₅; n-C₅H₁₁; mixed C₅H₁₇; n-C₁₂H₂₅; n-C₁₈H₃₇; mixed C₈-C₁₀alkyl; and the like. However, R^(A) may also be selected from C₂H₅n-C₃H₇and n-C₄H₉ benzyl.

Various counterions may be used, including Cl⁻, Br⁻, I⁻, NO₃ ⁻, SO₄ ⁻²,HSO₄ ⁻ and CH₂CO₂ ⁻. Most preferred is Cl⁻.

The tertiary amines or triamines useful as phase transfer catalysts inthis synthesis include the alkyl amines and the aryidialkylamines,exemplified by tributylamine and phenyldibutylamine respectively, whichare commonly available, wherein each alkyl may have from 1 to about 16carbon atoms.

The polyethers useful as catalysts in this synthesis include cyclicpolyethers such as the crown ethers, disclosed in Agenwandte Chemie,supra, and acyclic polyethers having the formulaR—O—R^(E)wherein R and R^(E) are, independently, alkyls having from 1 to about 16carbon atoms, or alkyl containing substituted functional groups such ashydroxy, sulfur, amine, ether, etc. Most preferred acyclic polyethershave the formulaR—(OCH₂CH₂), OR″wherein

-   -   R is an allyl having from 1 to about 16 carbon atoms    -   R″ is an alkyl having from 1 to about 16 carbon atoms, or H, and    -   r is an integer in the range from 0 to about 300.        Most preferred are commonly available polyethers such as:        tetraethylene glycol dimethyl ether; polyethylene oxide (mol wt.        About 5000); poly(ethylene glycol methyl ether);        1,2-dimethoxyethane; diethyl ether, and the like.

Polyether catalysts are especially desirable in this ketoform synthesisbecause they are directive so as to produce a preponderance of thedesired symmetrically substituted isomer, in a reaction which isremarkably free of undesirable byproducts, which reaction proceeds witha relatively mild exotherm so that the reaction is controllable.

The organic solvent may be any solvent in which the reactants aresoluble and include hydrohalomethylenes, particularlyhydrochloromethylenes, sulfolane, dibutyl ether, dimethyl sulfone,diisopropyl ether, di-n-propyl ether, 1,4-dioxane, tetrahydrofuran,benzene, toluene, hexane, carbon tetrachloride, heptane, mineral spiritsand the like. Most preferred solvents are heptanes and mineral spirits.Solvent is generally utilized in an amount generally from about 10 toabout 500 percent and preferably from about 50 percent to about 200percent based on the total weight of the reactants.

Insofar as the reactive components are concerned, any of various ketoneshaving the general formula:

can be employed in the synthesis, wherein R¹ and R² are described hereinabove. As carbon disulfide is the controlling agent in the reaction, theketone is generally used in an amount from about 110 mole percent toabout 2,000 mole percent per mole of carbon disulfide. When the ketoneis used as a solvent, it is generally utilized in an amount of fromabout 150 mole percent to about 300 mole percent, and preferably fromabout 180 mole percent to about 250 mole percent per mole of carbondisulfide.

The alkali bases suitable for use in the synthesis of the presentinvention include, but are not limited to, sodium hydroxide andpotassium hydroxide. The base is utilized in an amount generally fromabout 5 times to about 15 times the number of moles of carbon disulfideand preferably from about 6 to about 10 times the number of moles ofcarbon disulfide utilized in the reaction.

The acids used in the acidification step include, but are not limitedto, hydrochloric acid, sulfuric acid, phosphoric acid, etc. The acidsare utilized in amounts suitable to make the aqueous solution acidic.

The haloform of the present invention has the general formula CHX₃wherein X is, independently, chlorine or bromine. The amount of haloformused in the present invention is generally from about 110 mole percentto about 2000 mole percent, desirably from about 150 mole percent toabout 300 mole percent, and preferably 180 mole percent to about 250mole percent per mole of carbon disulfide. Examples of haloformsinclude, but are not limited to, chloroform and bromoform, andchloroform is the preferred haloform of the present invention.

Alternatively, instead of adding both a haloform and a ketone, to thereaction mixture, an α-trihalomethyl-α-alkanol can be substitutedtherefore. The amount of α-trihalomethyl-α-alkanol utilized in thereaction generally is from about 110 mole percent to about 2000 molepercent, desirably is from about 150 mole percent to about 300 molepercent, and preferably is from about 180 mole percent to about 250 molepercent per mole of carbon disulfide. The general formula of theα-trihalomethyl-α-alkanol is generally represented as follows:

wherein X, R¹ and R² are defined above.

While not wishing to be limited to any particular mechanism, it isbelieved that the specific mechanism for the reaction process is asfollows:

Initially, the carbon disulfide and sodium hydroxide are reacted.

In the subsequent step of the reaction, the chloroform is reacted withthe ketone as follows:

-   -   (1-disubstituted-2-dichloroepoxide)

Then, the following is reacted:

The overall reaction is as follows:

The s,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonatecompounds produced by the present invention can generally be classifiedas inifertors, meaning that they act as both a chain transfer agent andan initiator. The use of other types of inifertors for block copolymerswas discussed by Yagei and Schnabel in Progress in Polymer Science 15,551 (1990) and is hereby fully incorporated by reference.

Thus, the compounds of the present invention can be utilized asinitiators to initiate or start the polymerization of a monomer. Theycan also act as a chain transfer agent, which interrupts and terminatesthe growth of a polymer chain by formation of a new radical which canact as a nucleus for forming a new polymer chain. The compounds can alsobe utilized as terminators in that when most of initiating radicals andmonomers are consumed, the compounds are incorporated in the polymers asa dormant species. Desirably though, another compound, such as thoselisted herein below, is often used as an initiator in the free radicalpolymerization process as described herein below, and thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundsof the present invention will act as a chain-transfer agent.

The s,s′-bis-(α,α′-disubstituted-α″-acetic acid) trithiocarbonatecompounds of the present invention can be used as chain transfer agentsin a free radical polymerization process to provide polymerizationswhich have living characteristics and polymers of controlled molecularweight and low polydispersity, as well as for forming telechelicpolymers.

A living polymerization is a chain polymerization which proceeds in theabsence of termination and chain transfer. The following experimentalcriteria can be utilized to diagnose a living polymerization.

-   1. Polymerization proceeds until all monomer has been consumed.    Further addition of monomer results in continued polymerization.-   2. The number average molecular weight, M_(n) (or X_(n), the number    average degree of polymerization), is a linear function of    conversion.-   3. The number of polymer molecules (and active centres) is constant    and independent of conversion.-   4. The molecular weight can be controlled by the stoichiometry of    the reaction.-   5. Narrow molecular weight distribution polymers are produced.-   6. Chain-end functionalized polymers can be prepared in quantitative    yields.-   7. In radical polymerization, the number of active end groups should    be 2, one for each end.

Besides those mentioned above, other criteria can also help to determinethe living character of polymerization. For radical livingpolymerization, one is the ability of the polymer isolated from thefirst step of polymerization to be used as a macroinitiator for thesecond step of a polymerization in which block copolymers or graftedpolymers are ultimately formed. To confirm the formation of blockcopolymers, measurements of molecular weights and a determination of thestructure of the blocks are employed. For structure measurements, theexamination of NMR or IR signals for the segments where individualblocks are linked together and a determination of the end groups areboth very important. In radical polymerization, only some of thecriteria for living polymerizations are actually fulfilled. Due to theirability to undergo further polymerization, these types of polymers canalso be called ‘reactive polymers’. A more detailed description ofliving polymerization can be found in “Living Free-Radical BlockCopolymerization Using Thio-Inifertors”, by Anton Sebenik, Progress inPolymer Science, vol. 23, p. 876, 1998.

The living polymerization processes can be used to produce polymers ofnarrow molecular weight distribution containing one or more monomerssequences whose length and composition are controlled by thestoichiometery of the reaction and degree of conversion. Homopolymers,random copolymers or block polymers can be produced with a high degreeof control and with low polydispersity. Low polydispersity polymers arethose with polydispersities that are significantly less than thoseproduced by conventional free radical polymerization. In conventionalfree radical polymerization, polydispersities (polydispersity is definedas the ratio of the weight average to the number average molecularweight. M_(w)/M_(n)) of the polymers formed are typically greater than2.0. Polydispersities obtained by utilizing thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundsand derivatives thereof of the present invention are preferably 1.75 or1.5, or less, often 1.3 or less, and, with appropriate choice of thechain transfer agent and the reaction conditions, can be 1.25 or less.

When the s,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonatescompounds are utilized only as chain-transfer agents, the polymerizationcan be initiated with other initiators at lower temperature whileyielding polymers with similarly controlled fashion.

Free radical polymerizations utilizing thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundsas both initiators and chain transfer agents generally form telechelicpolymers. When an initiator other than thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundis also utilized, a polymer having a single functional end group isformed in proportion to the amount of said other initiator to thiss,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundutilized.

The free radical living polymerization process of the invention can beapplied to any monomers or monomer combinations which can befree-radically polymerized. Such monomers include one or more conjugateddiene monomers or one or more and vinyl containing monomers, orcombinations thereof.

The diene monomers have a total of from 4 to 12 carbon atoms andexamples include, but are not limited to, 1,3-butadine, isoprene,1,3-pentadiene, 2,3-dimethyl-1-3-butadiene, 2-methyl-1,3-pentadiene,2,3-dimethyl-1,3-pentadiene, 2-phenyl-1,3-butadiene, and4,5-diethyl-1,3-octadiene, and combinations thereof.

The vinyl containing monomers have the following structure:

where R³ comprises hydrogen, halogen, C₁ to C₄ alkyl, or substitutedC₁-C₄ alkyl wherein the substituents, independently, comprise one ormore hydroxy, alkoxy, aryloxy(OR⁵), carboxy, acyloxy, aroyloxy(O₂CR⁵),alkoxy-carbonyl(CO₂R⁵), or aryloxy-carbonyl; and R⁴ comprises hydrogen,R⁵, CO₂H, CO₂R⁵, COR⁵, CN, CONH₂, CONHR⁵, O₂CR⁵, OR⁵, or halogen. R⁵comprises C₁ to C₁₈ alkyl, substituted C₁-C₁₈ allyl, C₂-C₁₈ alkenyl,aryl, heterocyclyl, aralkyl, or alkaryl, wherein the substituentsindependently comprise one or more epoxy, hydroxy, alkoxy, acyl,acyloxy, carboxy, (and salts), sulfonic acid (and salts), alkoxy- oraryloxy-carbonyl, sicyanato, cyano, silyl, halo and dialkylamino.Optionally, the monomers comprise maleic anhydride, N-vinyl pyrrolidone,N-alkylmaleimide, N-arylmaleimide, diallyl fumarate andcyclopolymerizable monomers. Monomers CH₂═CR³R⁴ as used herein includeC₁-C₈ acrylates and methacrylates, acrylate and methacrylate esters,acrylic and methacrylic acid, styrene, a methyl styrene, C₁, —C₁₂ alkylstyrenes with substitute groups both either on the chain or on the ring,acrylamide, methacrylamide, and methacrylonitrile, mixtures of thesemonomers, and mixtures of these monomers with other monomers. As oneskilled in the art would recognize, the choice of comonomers isdetermined by their steric and electronic properties. The factors whichdetermine copolymerizability of various monomers are well documented inthe art. For example, see: Greenley, R. Z., in Polymer Handbook, 3^(rd)Edition (Brandup, J., and Immergut, E. H. Eds.) Wiley: New York, 1989pII/53.

Specific monomers or comonomers include the following: methylmethacrylate, ethyl methacrylate, propyl methacrylate (all isomers),butyl methacrylate (all isomers), 2-ethylhexyl methacrylate, isobornylmethacrylate, methacrylic acid, benzyl methacrylate, phenylmethacrylate, methacrylonitrile, alpha-methylstyrene. methyl acrylate,ethyl acrylate, propyl acrylate (all isomers), butyl acrylate (allisomers), 2-ethylhexyl acrylate, isobornyl acrylate, acrylic acid,benzyl acrylate, phenyl acrylate, acrylonitrile. styrene, functionalmethacrylates, acrylates and styrenes selected from glycidylmethacrylate, 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate(all isomers), hydroxybutyl methacrylate (all isomers),N,N-dimethylaminoethyl methacrylate, N,N-diethylaminoethyl methacrylate,triethyleneglycol methacrylate, itaconic anhydride, itaconic acid,glycidyl acrylate, 2-hydroxyethyl acrylate, hydroxypropyl acrylate (allisomers), hydroxybutyl acrylate (all isomers), N,N-dimethylaminoethylacrylate, N,N-diethylaminoethyl acrylate, triethyleneglycol acrylate,methacrylamide, N-methylacrylamide, N,N-dimethylacrylamide,N-tertbutylmethacrylamide, N-n-butylmethacrylamide,N-methylolmethacrylamide, N-ethylolmethacrylamide.N-tert-butylacrylamide. N-n-butylacrylamide, N-methylolacrylamide,N-ethylolacrylamide, vinyl benzoic acid (all isomers),dethylaminostyrene (all isomers), alpha-methylvinyl benzoic acid (allisomers), diethylamino alpha-methylstyrene (all isomers). p-vinylbenzenesulfonic acid, p-vinylbenzene sulfonic sodium salt,trimethoxysilylpropyl methacrylate, triethoxysilylpropyl methacrylate,tributoxysilylpropyl methacrylate, dimethoxymethylsilylpropylmethacrylate, diethoxymethylsilylpropyl methacrylate,dibutoxymethylsilylpropyl methacrylate, diisopropoxymethylsilylpropylmethacrylate, dimethoxysilylpropyl methacrylate, diethoxysilylpropylmethacrylate, dibutoxy, silylpropyl methacrylate,diisopropoxysilylpropyl methacrylate, trimethoxysilylpropyl acrylate,triethoxysilylylpropyl acrylate, tributoxysilylpropyl acrylate,dimethoxymethylsilylpropyl acrylate, diethoxymethylsilylpropyl acrylate,dibutoxymethylsilylpropyl acrylate, diisopropoxymethylsilylpropylacrylate, dimethoxysilylpropyl acrylate, diethoxysilylpropyl acrylate,dibutoxysilylpropyl acrylate, diisopropoxysilylpropyl amidate, vinylacetate, vinyl butyrate, vinyl benzoate, vinyl chloride, vinyl fluoride,vinyl bromide, maleic anhydride, N-phenylmaleimide, N-butylmaleimide,N-vinylpyrrolidone, N-vinylcarbazole, butadiene, isoprene, chloroprene,ethylene, and propylene, and combinations thereof.

Preferred monomers are C₁-C₈ acrylates, C₁-C₈ methacrylates, styrene,butadiene, isoprene and acrylonitrile.

As noted above, in order to initiate the free radical polymerizationprocess, it is often desirable to utilize an initiator as a source forinitiating free radicals. Generally, the source of initiating radicalscan be any suitable method of generating free radicals such as thethermally induced homolytic scission of a suitable compound(s) (thermalinitiators such as peroxides, peroxyesters, or azo compounds), thespontaneous generation from monomer (e.g., styrene), redox initiatingsystems, photochemical initiating systems or high energy radiation suchas electron beam, X- or gamma-radiation. The initiating system is chosensuch that under the reaction conditions there is no substantial adverseinteraction of the initiator or the initiating radicals with thetransfer agent under the conditions of the experiment. The initiatorshould also have the requisite solubility in the reaction medium ormonomer mixture. The s,s′-bis-(α,α′-disubstituted-α″-aceticacid)-trithiocarbonate compounds of the invention can serve as aninitiator, but the reaction must be run at a higher temperature.Therefore, optionally it is desirable to utilize an initiator other thanthe s,s′-bis-(α, α′-disubstituted-α″-acetic acid)-trithiocarbonatescompounds of the present invention.

Thermal initiators are chosen to have an appropriate half-life at thetemperature of polymerization. These initiators can include one or moreof the following compounds:

2,2′-azobis(isobutyronitrile)(AIBN), 2,2′-azobis(2-cyano-2-butane),dimethyl 2,2′-azobisdimethylisobutyrate, 4,4′-azobis(4-cyanopentanoicacid), 1,1′-azobis(cyclohexanecarbonitrile),2-(t-butylazo)-2-cyanopropane,2,2′-azobis[2-methyl-N-(1,1)-bis(hydroxymethyl)-2-hydroxyethyl]propionamide,2,2′-azobis[2-methyl-N-hydroxyethyl)]-propionamide,2,2′-azobis(N,N′-dimethyleneisobutyramidine) dihydrochloride,2,2′-azobis(2-amidinopropane) dihydrochloride,2,2′-azobis(N,N′-dimethyleneisobutyramine),2,2′-azobis(2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide),2,2′-azobis(2-methyl-N-[1,1-bis(hydroxymethyl)ethyl]propionamide),2,2′-azobis[2-methyl-N-(2-hydroxyethyl)propionamide],2,2′-azobis(isobutyramide) dehydrate,2,2′-azobis(2,2,4-trimethylpentane), 2,2′-azobis(2-methylpropane),t-butyl peroxyacetate, t-butyl peroxybenzoate, t-butyl peroxyoctoate,t-butylperoxyneodecanoate, t-butylperoxy isobutyrate, t-amylperoxypivalate, t-butyl peroxypivalate, di-isopropyl peroxydicarbonate,dicyclohexyl peroxydicarbonate, dicumyl peroxide, dibenzoyl peroxide,dilauroylperoxide, potassium peroxydisulfate, ammonium peroxydisulfate,di-t-butyl hyponitrite, dicumyl hyponitrite.

Photochemical initiator systems are chosen to have the requisitesolubility in the reaction medium or monomer mixture and have anappropriate quantum yield for radical production under the conditions ofthe polymerization. Examples include benzoin derivatives, benzophenone,acyl phosphine oxides, and photo-redox systems production under theconditions of the polymerization; these initiating systems can includecombinations of the following oxidants and reductants:

-   -   oxidants: potassium peroxydisulfate, hydrogen peroxide, t-butyl        hydroperoxide reductants: iron (11), titanium (111), potassium        thiosulfate, potassium bisulfite.

Other suitable initiating systems are described in recent texts. See,for example, Moad and Solomon “The Chemistry of Free RadicalPolymerization”. Pergamon, London. 1995. pp 53-95.

The preferred initiators of the present invention are2,2′-azobis(isobutyronitrile)(AIBN), or 4,4′-azobis(4-cyanopentanoicacid), or 2,2′-azobis(2-cyano-2-butane), or1,1′-azobis(cyclohexanecarbanitrile). The amount of initiators utilizedin the polymerization process can vary widely as generally from about0.001 percent to about 99 percent, and desirably from about 0.01 percentto about 50 or 75 percent based on the total moles of chain transferagent utilized. Preferably small amounts are utilized from about 0.1percent to about 5, 10, 15, 20, or 25 mole percent based on the totalmoles of chain transfer agent utilized, i.e. saids,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compounds.In order to form polymers which are predominately telechelic, initiatorsother than the s,s′-bis-(α,α′-disubstituted-α″-aceticacid)-trithiocarbonate compounds are utilized in lesser amounts, such asfrom about 0.001 percent to about 5 percent, desirably from about 0.01percent to about 4.5 percent, and preferably from about 0.1 percent toabout 3 percent based on the molar equivalent to the total moles ofchain transfer agent utilized.

Optionally, as noted above, solvents may be utilized in the free radicalpolymerization process. Examples of such solvents include, but are notlimited to, C₆-C₁₂ alkanes, toluene, chlorobenzene, acetone, t-butylalcohol, and dimethylformamide. The solvents are chosen so that they donot chain transfer themselves. The amount of solvent utilized in thepresent invention polymerization process is generally from about 10percent to about 500 percent the weight of the monomer, and preferablyfrom about 50 percent to about 200 percent the weight of the monomerutilized in the polymerization.

As stated above, it is preferable to utilize thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundsof the invention as chain transfer agents in the free radicalpolymerization process. The amount of chain transfer agent (CTA)utilized depends on the desired molecular weight of the polymer to beformed and can be calculated as known by one skilled in the art. Aformula for calculating the amount of chain transfer agent is asfollows: $\begin{matrix}{{{Mn}\quad{of}\quad{polymer}} = {\left( {\frac{{Weight}\quad{of}\quad{monomer} \times {molecular}\quad{weight}}{{Weight}\quad{of}\quad{CTA}}{CTA}} \right) + {{molecular}\quad{weight}\quad{of}\quad{CTA}}}} & {{XII}\quad(a)}\end{matrix}$

While not wishing to be limited to any particular mechanism, it isbelieved that the mechanism of the free radical living polymerizationprocess is as follows when using a vinyl monomer:

Alternatively, the reaction can proceed as follows:

As can be seen from the above mechanism, polymers having two differentstructures, see XIX and XXII, can be formed. The resulting polymers areeither telechelic polymers (formed by the trithiocarbonate compounds ofthe present invention) with identical functional groups at the ends ofthe chain, or a polymer having a single functional end group and also aninitiator terminated chain (formed by using a conventional initiatorsuch as AIBN). As stated above, the ratios between the resultingpolymers can be controlled to give desired results and generally dependson the amount of initiator utilized. Obviously, if the initiator is theonly s,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonatecompound of the present invention, the resulting polymers are alwaystelechelic. The greater the amount of the other initiator utilized,proportionally decreases the amount of telechelic polymers formed.Generally, the amount of the repeat group m, m′, m″, n, n′, or n″, isgenerally from about 1 to about 10,000, desirably from about 5 to about500, and preferably from about 10 to about 200. Inasmuch as one or morevinyl monomers and/or one or more diene monomers can be utilized, it isto be understood that repeat groups of the polymers of the presentinvention are generally indicated by formulas XIX and XXII and can bethe same or different. That is, random copolymers, terpolymers, etc.,can be formed within either of the two repeat groups noted, as well asblock copolymers which can be formed by initially adding one monomer andthen subsequently adding a different monomer (e.g. an internal blockcopolymer).

The polymers formed by the present invention can be generallyrepresented by the following formula:

wherein such monomers are described herein above. Of course, the aboveformula can contain an initiator end group thereon as in XXII.

The reaction conditions are chosen as known to one skilled in the art sothat the temperature utilized will generate a radical in a controlledfashion, wherein the temperature is generally from about roomtemperature to about 200° C. The reaction can be run at temperatureslower than room temperature, but it is impractical to do so. Thetemperature often depends on the initiator chosen for the reaction, forexample, when AIBN is utilized, the temperature generally is from about40° C. to about 80° C., when azo dicyanodivaleric acid is utilized, thetemperature generally is from about 50° C. to about 90° C., whendi-t-butylperoxide is utilized, the temperature generally is from about110° C. to about 160° C., when s,s′-bis-(α, α′-disubstituted-α″-aceticacid) is utilized, the temperature is generally from about 80° C. toabout 200° C.

The low polydispersity polymers prepared as stated above by the freeradical polymerization can contain reactive end groups from the monomerswhich are able to undergo further chemical transformation or reactionsuch as being joined with another polymer chain, such as to form blockcopolymers for example. Therefore, any of the above listed monomers,i.e. conjugated dienes or vinyl containing monomers, can be utilized toform block copolymers utilizing the s,s′-bis-(α,α′-distributed-α″-aceticacid)-trithiocarbonate compounds as chain transfer agent. Alternatively,the substituents may be non-reactive such as alkoxy, alkyl, or aryl.Reactive groups should be chosen such that there is no adverse reactionwith the chain transfer agents under the conditions of the experiment.

The process of this invention can be carried out in emulsion, solutionor suspension in either a batch, semi-batch, continuous, or feed mode.Otherwise-conventional procedures can be used to produce narrowpolydispersity polymers. For lowest polydispersity polymers, the chaintransfer agent is added before polymerization is commenced. For example,when carried out in batch mode in solution, the reactor is typicallycharged with chain transfer agent and monomer or medium plus monomer.The desired amount of initiator is then added to the mixture and themixture is heated for a time which is dictated by the desired conversionand molecular weight. Polymers with broad, yet controlled,polydispersity or with multimodal molecular weight distribution can beproduced by controlled addition of the chain transfer agent over thecourse of the polymerization process.

In the case of emulsion or suspension polymerization the medium willoften be predominately water and the conventional stabilizers,dispersants and other additives can be present. For solutionpolymerization, the reaction medium can be chosen from a wide range ofmedia to suit the monomer(s) being used.

As already stated, the use of feed polymerization conditions allows theuse of chain transfer agents with lower transfer constants and allowsthe synthesis of block polymers that are not readily achieved usingbatch polymerization processes. If the polymerization is carried out asa feed system the reaction can be carried out as follows. The reactor ischarged with the chosen medium, the chain transfer agent and optionallya portion of the monomer(s). The remaining monomer(s) is placed into aseparate vessel. Initiator is dissolved or suspended in the reactionmedium in another separate vessel. The medium in the reactor is heatedand stirred while the monomer+medium and initiator+medium are introducedover time, for example by a syringe pump or other pumping device. Therate and duration of feed is determined largely by the quantity ofsolution the desired monomer/chain transfer agent/initiator ratio andthe rate of the polymerization. When the feed is complete, heating canbe continued for an additional period.

Following completion of the polymerization, the polymer can be isolatedby stripping off the medium and unreacted monomer(s) or by precipitationwith a non-solvent. Alternatively, the polymer solution/emulsion can beused as such, if appropriate to its application.

The invention has wide applicability in the field of free radicalpolymerization and can be used to produce polymers and compositions forcoatings, including clear coats and base coat finishes for paints forautomobiles and other vehicles or industrial, architectural ormaintenance finishes for a wide variety of substrates. Such coatings canfurther include pigments, durability agents, corrosion and oxidationinhibitors, rheology control agents, metallic flakes and otheradditives. Block and star, and branched polymers can be used ascompatibilizers, thermoplastic elastomers, dispersing agents or rheologycontrol agents. Additional applications for polymers of the inventionare in the fields of imaging, electronics (e.g., photoresists),engineering plastics, adhesives, sealants, paper coatings andtreatments, textile coatings and treatments, inks and overprintvarnishes, and polymers in general.

As can be seen in the above shown polymerization mechanism, thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundcan be utilized to create telechelic polymers having two functionalgroups at both chain ends.

The term “telechelic polymer” was proposed in 1960 by Uraneck et al. todesignate relatively low molecular weight macromolecules possessing oneor more, and preferably two reactive functional groups, situated at thechain ends, thereof. The functional end groups of both thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundand the polymers formed therefrom, have the capacity for selectivereaction to form bonds with another molecule. The functionality of atelechelic polymer or prepolymer is equal to the number of such endgroups. Telechelic polymers containing a functional group, such as COOH,at each end are useful for synthesizing further chain extendedcopolymers and block copolymers.

The interest in telechelic polymers resides in the fact that suchpolymers can be used, generally together with suitable linking agents,to carry out three important operations: (1) chain extension of shortchains to long ones by means of bifunctional linking agents, (2)formation of networks by use of multifunctional linking agents, and (3)formation of (poly)block copolymers by combination of telechelics withdifferent backbones. These concepts are of great industrial importancesince they form the basis of the so-called “liquid polymer” technologyexemplified by the “reaction injection molding” (RIM). Great interesthas also been shown by the rubber industry because the formation of arubber is based on network formation. In classical rubber technology,this is achieved by the cross-linking of long chains that show highviscosity. The classical rubber technology, therefore, requires anenergy-intensive mixing operation. The use of liquid precursors, whichcan be end-linked to the desired network, offers not only processingadvantages, but in some cases, also better properties of theend-product. Further information about telechelic polymers and synthesisthereof can be found in “Telechelic Polymers: Synthesis andApplications” by Eric J. Goethe, CRC Press, Boca Raton, Fla., 1989.

The reaction conditions for the reactive functional acid end groups ofthe telechelic polymers or s,s′-bis-(α,α′-disubstituted-α″-aceticacid)-trithiocarbonate compounds of the present invention are generallythe same as those for forming the above noted free radical polymers. Theacid in the monomeric or in the polymeric form can be transformed to itsderivatives in the conventional manner. For example, the ester can bemade by refluxing the acid in alcohol with an acid catalyst with removalof water. Amides can be formed by heating the acid with an amine withthe removal of water. 2-hydroxy-ethyl ester can be formed by directlyreacting the acid with an epoxide with or without a catalyst such astriphenylphosphine or an acid like toluene-sulfonic acid. As seen by theexamples below, any of the above noted monomers such as the one or morediene monomers or one or more vinyl containing monomers, can be utilizedto form the telechelic monomers from the bis-(α,α′-distributed-α″-aceticacid)-trithiocarbonate compounds of the present invention. Any of theabove noted components, such as solvent, etc., can be utilized in theherein above stated amounts.

The acid groups of the s,s′-bis-(α,α′-disubstituted-α″-aceticacid)-trithiocarbonate compound can be converted to other functionalgroups either before or after polymerization. Even if thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundshave functional end groups which have been converted from the acid endgroups before polymerization, the monomers added during polymerizationstill add to the chain between the sulfur-tertiary carbon as shown inthe mechanisms above as well as below at XXIII and XXIV. The carboxylicend groups of the s,s′-bis-(α,α′-disubstituted-α″-aceticacid)-trithiocarbonate compounds or the polymerizeds,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundscan be converted or changed into other functional end groups such asesters, thioesters, amides, beta mercapto esters, beta hydroxy esters,or beta amino esters. Examples of these functional end groups are shownbelow.

An example reaction forming a telechelic polymer from thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundsof the invention when using a vinyl monomer is as follows:

Of course, it is to be understood as indicated above, that the repeatunits m and n can be derived either from conjugated diene monomers, orthe indicated vinyl monomers, or combinations thereof, as generally setforth in formula W.

Subsequently, other functional end groups can be derived from the acidgroups of the s,s′-bis-(α,α′-disubstituted-α″-aceticacid)-trithiocarbonate compound and can generally be represented by theformula:

where E is set forth below. For example,

wherein E is XR′, that is R′, independently, comprises H, C₁-C₁₈ alkylswhich can be optionally substituted with one or more halogen, hydroxyl,or alkoxy, C₁-C₁₈ hydroxyalkyls, and C₁-C₁₈ aminoalkyls and X comprisesoxygen, sulfur, NH, or NR′.

The following is still another example of functional end groups whichcan be derived from the acid:

wherein E is

that is where R⁶ through R⁹, independently comprise H, C₁-C₁₈ alkyls,aryl groups or substituted aryl groups having from 1 to 6 substituentson the ring, such as halogen, hydroxyl, or alkoxy, C₁-C₁₈ hydroxyalkys,C₁-C₁₈ aminoalkyls, C₁-C₁₈ mercapto alkyls, and the like. Y can compriseoxygen, sulfur, NH, or NR⁶ to R⁹.

A further example of still other functional end groups which can bederived from the acid groups of thes,s′-bis-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate compoundsis as follows:

wherein E is OR¹⁰, that is where Z can comprise a leaving group, such asa halide or alkylsulfonate or aryl sulfonate. R¹⁰ can comprise C₁-C₁₈, aalkyl or substituted allyl wherein said substituent is halogen,hydroxyl, or alkoxy, C₁-C₁₈ hydroxyalkyl or C₁-C₁₈ amino alkyl and thelike.

Preparation of the above shown methylesters ofs,s′-bis-(2-methyl-2-propanoic acid)-trithiocarbonate is as follows:s,s′-bis-(2-methyl-2-propanoic acid) trithiocarbonate (R¹,R²═CH³) (2.82g, 0.01 mole), Sodium carbonate powders (3.18 g, 0.03 mole) and 15 mldimethyl formamide were stirred under nitrogen at 40° C. while asolution of methyliodide (3.41 g, 0.024 mole) in 2 ml dimethylformamidewas added dropwise over 10 minutes. The reaction was stirred at 40-50°C. for 2 hours, poured into 25 ml H₂O and extracted 3 times with a totalof 200 ml. ether. The etherate solution was dried over magnesium sulfateand concentrated. The yellow solid was further purified byrecrystallization from hexanes. Infrared and H′NMR showed the abovedesired product.

An example of an already formed telechelic polymer, made from a vinylmonomer, undergoing conversion of the acid end group is as follows:

where m and n are as set forth above.

The above structure (XXXIV) was formed by reaction of epoxide withs,s′-bis-(2-methyl-2-propanoic acid)-trithiocarbonate (I)(R¹,R²═CH₃,0.01 mole) of the present invention and Epon® Resin 828 (ResolutionPerformance Products, reaction product of bisphenol A andepichlorohydrin, 80-85% diglycidyl ethers of bisphenol A) (70 g) andtriphenyl phosphine (0.12 g) were heated to 95° C. under nitrogen. Thereaction was monitored for the disappearance of the carboxylic acid bytitration. It was found the reaction was essentially complete in 1.5hours. The product structure can be further confirmed by massspectroscopy.

Another aspect of present invention further relates to forming thefollowing compounds:

wherein R¹¹ comprises a benzyl group, C₁-C₁₈ alkyl, or substituted alkylsuch as halogen, hydroxyl, or alkoxy, C₁-C₁₈ hydroxyalkyl,carboxylalkyl, or carboalkoxyalkyl. Q⁺X⁻ is a phase transfer catalystsuch as tetrabutylammoniumhydrogensulfate, oroctadecyltrimethylammoniumchloride (Aliquot 336).

The resulting compound is an s-substitutedallyl-s′-(α,α′-disubstituted-α″-acetic acid)-trithiocarbonate. R¹¹ is analkyl having from 1-18 carbon atoms, aralkyl, hydroxyalkyl, cyanoalkyl,aminoalkyl, carboxylalkyl, or carboalkoxyalkyl, mercaptoalkyl, etc. R¹and R² are as stated herein above.

When s-substituted alkyl-s′-(α,α′-disubstituted-α″-aceticacid)-trithiocarbonate is employed either as an inifertor, or as achain-transfer agent, unless R¹¹ is carboxyl alkyl, only one end of thepolymer has a carboxyl function, i.e. it is no longer a telechelicpolymer.

While various polymers have been set forth herein above, it is to beunderstood that any of the carboxyl terminated polymers, such as W, orthe E terminated polymers, and the like, can be reacted with one or moremonomers and/or one or more polymers know to the art and to theliterature to yield various resulting block polymers which are derivedfrom the same monomer or from two or more different monomers. Forexample, each acid end group can be reacted with an excess of an epoxycompound such as a glycidyl bisphenol A and then Subsequentlypolymerized with additional glycidyl bisphenol A to form an epoxypolymer. Naturally, other block polymers or copolymers can be reactedwith the carboxylic end group or the other end groups generally denotedby E hereinabove.

A further embodiment of the present invention relates to dithiocarbonatecompounds which have the general formula:

wherein D is

OR¹⁴),

NR¹⁵R¹⁶);

wherein R¹ and R¹³, independently, can be the same or different, canoptionally be substituted, and can be a linear or branched alkyl havingfrom 1 to about 6 or about 12 carbon atoms; or an aryl group having from6 to about 18 carbon atoms, optionally containing heteroatoms;

The R¹² and/or R¹³ substituents can, independently, comprise an alkylhaving from 1 to 6 carbon atoms; an aryl group; a halogen; a cyanogroup; an ether having a total of from 2 to about 20 carbon atoms; anitro; or combinations thereof. R¹² and R³ can also form or be a part ofa substituted or unsubstituted cyclic ring having from 3 to about 12total carbon atoms wherein the substituents are described above. R¹² andR¹³ are preferably, independently, methyl or phenyl groups;

wherein R¹⁴ is optionally substituted, and can be a linear or branchedalkyl having from 1 to about 12 carbon atoms; an aryl group, optionallysaturated or unsaturated; an arylalkyl having from 7 to about 18 carbonatoms; an acyl group; an alkenealkyl having from 3 to about 18 carbonatoms; an alkene group; an alkylene group; an alkoxyalkyl; derived froma polyalkylene glycol; derived from a polyalkylene glycol monoalkylether having from 3 to 200 carbon atoms; derived from a polyalkyleneglycol monoaryl ether having from 3 to 200 carbon atoms; apolyfluoroalkyl such as 2-trifluoroethyl; a phosphorous containingallyl; or a substituted or unsubstituted aryl ring containingheteroatoms. Alkyl and alkylene groups from 1 to 6 carbon atoms arepreferred;

The R¹⁴ substituents can comprise an alkyl having from 1 to 6 carbonatoms; an aryl; a halogen such as fluorine or chlorine; a cyano group;an amino group; an alkene group; an alkoxycarbonyl group; anaryloxycarbonyl group; a carboxy group; an acyloxy group; a carbamoylgroup; an alkylcarbonyl group; an alkylarylcarbonyl group; anarylcarbonyl group; an arylalkylcarbonyl group; a phthalimido group; amaleimido group; a succinimido group; amidino group; guanidimo group;allyl group; epoxy group; alkoxy group; an alkali metal salt; a cationicsubstitutent such as a quaternary ammonium salt; a hydroxyl group; anether having a total of from 2 to about 20 carbon atoms such as methoxy,or hexanoxy; a nitro; sulfur; phosphorous; a carboalkoxy group; aheterocyclic group containing one or more sulfur, oxygen or nitrogenatoms, or combinations thereof;

wherein R¹⁵ and R¹⁶, independently, can be the same or different,optionally can be substituted, optionally can contain heteroatoms; andcan be hydrogen; a linear or branched alkyl having from 1 to about 18carbon atoms, an aryl group having from about 6 to about 18 carbonatoms; an arylalkyl having from about 7 to about 18 carbon atoms; analkenealkyl having from 3 to about 18 carbon atoms; or derived from apolyalkylene glycol ether having from 3 to about 200 carbon atoms. R¹⁵and R¹⁶ can also be derived from amines such as, but not limited to,piperazine, morpholine, pyrrolidine, piperidine, 4-alkylamino-2,2,6,6-tetramethyl piperidine,1-alkylaminoalkyl-3,3,5,5-tetramethyl-2-piperazinone,hexamethyleneimine, phenothiazine, iminodibenzyl, phenoxazine,N,N′-diphenyl-1,4-phenylenediamine, dicyclohexylamine and derivativesthereof. R¹⁵ and R¹⁶ can also form a substituted or unsubstituted cyclicring, optionally containing heteroatoms, along with the nitrogen havinga total of from 4 to about 12 carbon atoms, such as benzotriazole,tolyltriazole, imidazole, 2-oxazolidone, 4,4-dimethyloxazolidone and thelike. The R¹⁵ and R¹⁶ substituents, independently, can be the same asdescribed hereabove with respect to R¹⁴. R¹⁵ and R¹⁶ are preferably,independently, a phenyl group or an alkyl or substituted alkyl havingfrom 1 to about 18 carbon atoms such as a methyl group, or R¹⁵ and R¹⁶can be hexamethylene; and

wherein j is 1 to about 4, and preferably 1 or 2.

When j of the above formula is greater than 1, the compound formed willbe a dimer, trimer, etc. The dithiocarbonate derivative compounds andpolymers or copolymers formed from the compounds are thus di-, or tri-,or poly-carboxyl terminated. For example, dicarboxyl terminatedcompounds of the present invention can be derived from ethylene glycol,1,3-propanediol, 1,6-hexanediol, 2-methyl-1,3-propanediol,2,2′-dimethyl-1,3-propanediol, and the like.

It is to be understood throughout the application formulas, reactionschemes, mechanisms, etc., and the specification that metals such assodium or bases such as sodium hydroxide are referred to and theapplication of the present invention is not meant to be solely limitedthereto. Other metals or bases such as, but not limited to, potassiumand potassium hydroxide, respectively, are contemplated by thedisclosure of the present invention.

Dithiocarbamates

When D of above formula is

NR¹⁵R¹⁶), the dithiocarbonate compound is aS-(α,α′-disubstituted-α″-acetic acid) dithiocarbamate having thefollowing formula:

wherein R¹², R¹³, R¹⁵, R¹⁶ and j are as defined hereinabove.

The S-(α,α′-disubstituted-α″-acetic acid) dithiocarbamates are generallya reaction product of a metal salt of a dithiocarbamate, a haloform, anda ketone. A phase transfer catalyst, solvent, and a base such as sodiumhydroxide or potassium hydroxide can also be utilized to form theS-(α,α″-disubstituted-α″-acetic acid) dithiocarbamates.

The metal salt of a dithiocarbamate is either prepared or purchased froma supplier such as Aldrich of Milwaukee, Wis. or Acros of Sommerville,N.J. Metal salts of dithiocarbamates can be made in situ from amine,carbon disulfide, and a metal hydroxide as disclosed in the literature.Examples of metal salts of dithiocarbamates include sodium N,N-dimethyldithiocarbamate and sodium N,N-diethyl-dithiocarbamate.

The S-(α,α′-disubstituted-α″-acetic acid) dithiocarbamate is formed bycombining a metal salt of the dithiocarbamate with a haloform, a ketone,a base, optionally a solvent and a catalyst, in a reaction vesselpreferably under an inert atmosphere. The base is preferably added tothe other components over a period of time to maintain a preferredtemperature range and avoid by-products. The reaction product issubsequently acidified, completing the reaction. The reaction product isisolated as a solid or liquid and is optionally purified.

The limiting agents of the reaction are usually the amine and carbondisulfide, or the metal salt of the dithiocarbamate when utilized. Thehaloform is utilized in the reaction in an amount from about 0 percentto about 500 percent molar excess, with about 50 percent to about 200percent molar excess preferred. The ketone is utilized in the reactionin an amount from 0 percent to about 3000 percent molar excess, withabout 100 percent to about 1000 percent molar excess preferred. Themetal hydroxide when utilized, is present in an amount from 10 percentto 500 percent molar excess, with about 60 percent to 150 percent molarexcess preferred.

The abbreviated reaction formula for the S-(α,α′-disubstituted-α″-aceticacid) dithiocarbamate of the present invention is generally as follows:

The reaction is carried out at a temperature sufficient to initiate andcomplete reaction of the reactants in order to produce theS-(α,α′-disubstituted-α″-acetic acid) dithiocarbamate compound in adesired time. The reaction can be carried out at any temperature withina wide range of from about the freezing point of the reaction mass toabout the reflux temperature of the solvent. The reaction temperature isgenerally from about minus 15° C. to about 80° C., desirably from about0° C. to about 50° C., and preferably from about 15° C. to about 35° C.,with about 15° C. to about 25° C. being preferred. The reaction can beperformed at atmospheric pressure. The reaction time depends on severalfactors, with the temperature being most influential. The reaction isgenerally complete within 20 hours and preferably within about 10 hours.

A catalyst, preferably a phase transfer catalyst, is generally utilizedwhen the optional solvent is used in the reaction. Examples ofpreferable catalysts and solvents are listed hereinabove andincorporated by reference. Preferred phase transfer catalysts includetricaprylmethylammonium chloride (Aliquot 336), benzyltriethylammoniumchloride, and tetrabutylammonium hydrogen sulfate. The amount ofcatalyst and solvents utilized in the reaction to form theS-(α,α′-disubstituted-α″-acetic acid) dithiocarbamate compound aregenerally the same as set forth above and herein incorporated byreference. When the ketone is also the solvent, the catalyst isoptionally eliminated from the process.

The ketones, haloforms, bases, and acids utilized in the dithiocarbamatereaction can be the same as those listed above for the trithiocarbonatesynthesis and amounts thereof are herein incorporated by reference.Alternatively, an α-trihalomethyl-α-alkanol can be utilized in place ofthe haloform and ketone in the amounts noted hereinabove for thetrithiocarbonate synthesis.

It is believed that the reaction scheme for the formation of theS-(α,α′-disubstituted-α″-acetic acid) dithiocarbamate is as follows:

wherein R¹⁵ and R¹⁶ are defined hereinabove. A phase transfer catalystsuch as tetrabutylammoniumhydrogensulfate oroctadecyltrimethylammoniumchloride (Aliquot 336) as mentioned above canbe utilized.

The S-(α,α′-disubstituted-α″-acetic acid) dithiocarbamate compounds canbe utilized in essentially the same manner as the trithiocarbonatecompounds mentioned hereinabove. That is, theS-(α,α′-disubstituted-α″-acetic acid) dithiocarbamate compounds can beutilized as initiators to initiate or start the polymerization of amonomer, as a chain transfer agent which interrupts and terminates thegrowth of a polymer chain by formation of a new radical which can act asthe nucleus for forming a new polymer chain, and/or as a terminatorwhich are incorporated into a polymer as a dormant species. Preferably,the S-(α,α′-disubstituted-α″-acetic acid) dithiocarbamate compounds areutilized as chain transfer agents in free radical polymerizations havingliving characteristics to provide polymers of controlled molecularweight and low polydispersity.

Dithiocarbamate (Co)Polymers

To this end, the present invention also relates to both a process forforming polymers or copolymer derived from the dithiocarbamate compoundshaving the following general formula:

wherein R¹², R¹³, R¹⁵, R¹⁶ and j are defined hereinabove, wherein thepolymer is derived from a conjugated diene monomer, or a vinylcontaining monomer, or combinations thereof, as defined hereinabove andincorporated by reference, wherein each polymer repeat unit is the sameor different, and wherein f is generally from 1 to about 10,000, andpreferably from about 3 to about 5,000. Preferred polymers are alkylacrylate, vinyl acetate, acrylic acid, and styrene. Of course, it is tobe understood that when f is 1, the polymer is a single reacted monomerunit.

The above polymers or copolymers can be prepared by bringing intocontact with each other the monomer(s) which form(s) the (polymer)repeat units and S-(α,α′-disubstituted-α″-acetic acid)-dithiocarbamatecompound, and optionally a) solvent, and b) a radical polymerizationinitiator; in suitable amounts, as described hereinabove.

It is believed the mechanism is as follows:

As illustrated by the above reaction formulas, the monomers arepolymerized into the dithiocarbamate compounds adjacent to thethiocarbonylthio linkage, between the single bonded sulfur atom and thetertiary carbon atom of the compound.

The dithiocarbamate compounds of the present invention can be used toproduce polymers which are substantially colorless. The polymers orcopolymers of the dithiocarbamate compounds are hydrolytically stablebecause the electro-donating amino groups render the thiocarbonyl groupless electrophilic and the polymers are also stable toward nucleophilessuch as amines.

The reaction conditions are chosen as known to one skilled in the art sothat the temperature utilized will generate a radical in a controlledfashion with the temperature being generally from about room temperatureto about 200° C. The reaction can be performed at temperatures lowerthan room temperature, but it is impractical to do so. The temperatureoften depends on the initiator chosen for the reaction, for example,when AIBN is utilized, the temperature generally is from about 40° C. toabout 80° C., when azodicyanodivaleric acid is utilized, the temperaturegenerally is from about 50° C. to about 90° C., when di-t-butylperoxideis utilized, the temperature generally is from about 110° C. to about160° C., and when S-(α,α′-disubstituted-α″-acetic acid) dithiocarbamateis utilized, the temperature is generally from about 120° C. to about200° C.

The low polydispersity polymers prepared as stated above by the freeradical polymerization can contain reactive end groups from the monomerswhich are able to undergo further chemical transformation or reactionsuch as being joined with another polymer chain, such as to formcopolymers for example. Therefore, any of the above listed monomers,i.e. conjugated dienes or vinyl containing monomers, can be utilized toform copolymers utilizing the S-(α,α′-disubstituted-α″-acetic acid)dithiocarbamate compounds as chain transfer agent. Moreover, thepolymers can be crosslinked using a crosslinker during polymerization.Suitable crosslinkers include, but are not limited to, polyalkylpentaerythritol, polyalkyl sucrose, trimethylol propane diacrylate,trimethylol propane triacrylate, glycerol triacrylate, methylenebis-acrylamide and ethylene-glycol diacrylate. Alternatively, thesubstituents may be non-reactive such as alkoxy, alkyl, or aryl.Reactive groups should be chosen such that there is no adverse reactionwith the chain transfer agents under the conditions of the experiment.

The process of this invention can be carried out in emulsion, solutionor suspension in either a batch, semi-batch, continuous, or feed mode.Bulk polymerization (no solvent) can also be achieved becausepropagation is slower. Otherwise-conventional procedures can be used toproduce narrow polydispersity polymers. For lowest polydispersitypolymers, the chain transfer agent is added before polymerization iscommenced. The polydispersity of polymers or copolymers produced fromthe dithiocarbamates is generally less than about 3.0. For example, whencarried out in batch mode in solution, the reactor is typically chargedwith chain transfer agent and monomer or medium plus monomer. Thedesired amount of initiator is then added to the mixture and the mixtureis heated for a time which is dictated by the desired conversion andmolecular weight. Polymers with broad, yet controlled, polydispersity orwith multimodal molecular weight distribution can be produced bycontrolled addition of the chain transfer agent over the course of thepolymerization process.

In the case of emulsion or suspension polymerization the medium willoften be predominately water and the conventional stabilizers,dispersants and other additives can be present. For solutionpolymerization, the reaction medium can be chosen from a wide range ofmedia to suit the monomer(s) being used.

As already stated, the use of feed polymerization conditions allows theuse of chain transfer agents with lower transfer constants and allowsthe synthesis of block polymers that are not readily achieved usingbatch polymerization processes. If the polymerization is carried out asa feed system the reaction can be carried out as follows. The reactor ischarged with the chosen medium, the chain transfer agent and optionallya portion of the monomer(s). The remaining monomer(s) is placed into aseparate vessel. Initiator is dissolved or suspended in the reactionmedium in still another separate vessel. The medium in the reactor isheated and stirred while the monomer+medium and initiator+medium areintroduced over time, for example by a syringe pump or other pumpingdevice. The rate and duration of feed is determined largely by thequantity of solution the desired monomer/chain transfer agent/initiatorratio and the rate of the polymerization. When the feed is complete,heating can be continued for an additional period.

Following completion of the polymerization, the polymer can be isolatedby stripping off the medium and unreacted monomer(s) or by precipitationwith a non-solvent. Alternatively, the polymer solution/emulsion can beused as such, if appropriate to its application. The applications forthe S-(α,α′-disubstituted-α″-acetic acid) dithiocarbamate compoundsinclude any of those listed hereinabove with regard to thetrithiocarbonate compounds.

Derivatives of the dithiocarbamate polymers or copolymers can also beformed including esterification products from the alcohol and/or diolend groups present. Thioesters can be formed utilizing mercaptan, andamides can be formed from amines, etc. Ammonium salts can be formed fromprimary, secondary, and tertiary amines. Metal salts can be formed fromalkaline or alkaline earth hydroxides, oxides and the like.

The invention has wide applicability in the field of free radicalpolymerization and can be used to produce polymers and compositions forcoatings, including clear coats and base coat finishes for paints forautomobiles and other vehicles or industrial, architectural ormaintenance finishes for a wide variety of substrates. Such coatings canfurther include conventional additives such as pigments, durabilityagents, corrosion and oxidation inhibitors, rheology control agents,metallic flakes and other additives. Block, star, and branched polymerscan be used as compatibilizers, thermoplastic elastomers, dispersingagents or rheology control agents. Additional applications for polymersof the invention are in the fields of imaging, electronics (e.g.,photoresists), engineering plastics, adhesives, sealants, paper coatingsand treatments, textile coatings and treatments, inks and overprintvarnishes, and polymers in general.

Alkoxy Dithiocarbonates

Yet another embodiment of the present invention relates to alkoxydithiocarbonate compounds having the following formula:

wherein R¹², R¹³, and R¹⁴ are as defined hereinabove, and wherein “a” is1 to about 4 with 1 or 2 preferred.

The compounds of the above formula can also be generally identified asO-alkyl-S-(α,α′-disubstituted-α″-acetic acid) xanthates. TheO-alkyl-S-(α,α′-disubstituted-α″-acetic acid) xanthates are generated asthe reaction product of an alkoxylate salt, carbon disulfide, ahaloform, and a ketone. Alternatively, a metal salt of xanthate can beutilized in place of the alkoxylate salt and carbon disulfide.

The alkoxylate salt or carbon disulfide, or alternatively the metal saltof xanthate are typically the limiting agents for the reaction. Thehaloform is utilized in the reaction in an amount generally from 0percent to about 500 percent molar excess, and preferably from about 50to about 200 percent molar excess. The ketone is utilized in thereaction in an amount generally from 0 percent to about 3000 percentmolar excess, and preferably from about 100 percent to about 1000percent molar excess. The metal hydroxide when utilized, is present inan amount from 10 percent to 500 percent molar excess, with about 60percent to 150 percent molar excess preferred.

The general reaction mechanism for forming theO-allyl-S-(α,α′-disubstituted-α″-acetic acid) xanthates is as follows:

The preparation of the O-alkyl-S-(α,α′-disubstituted-α″-acetic acid)xanthates begins with the addition of a xanthate, i.e., a salt ofxanthic acid to a reaction vessel, preferably equipped with an agitatingdevice, thermometer, addition funnel, and a condenser. The xanthate canbe prepared from an alkoxylate salt and carbon disulfide as known in theart.

For example, the sodium salt of O-ethyl xanthate, CH₃CH₂OC(S)S⁻Na⁺, canbe prepared from sodium ethoxide and carbon disulfide in the presence ofa solvent such as an acetone, and optionally a catalyst, such as Aliquot336 or other catalyst stated herein or known in the art, in a reactionvessel, preferably at about 0° to about 25° C. The general reaction is:

The metal salt of O-ethyl xanthate is also commercially available fromsources such as Aldrich Chemical of Milwaukee, Wis.

In a further step, a ketone, a haloform, optionally a solvent, and acatalyst, all as described hereinabove, are added to the reaction vesselcontaining the xanthate metal salt. When the ketone is used as thesolvent, the catalyst is optionally eliminated from the process. Astrong base as noted hereinabove is added to the mixture, preferablyover an extended period of time. The reaction components are preferablymixed throughout the reaction. The reaction product is subsequentlyacidified with an acid as noted hereinabove, completing the reaction andforming the O-alkyl-S-(α,α′-disubstituted-α″-acetic acid) xanthate. Thereaction is conducted at a temperature generally from about 0° C. toabout 80° C., and preferably from about 15° C. to about 50° C., withroom temperature being preferred. The reaction can be performed atatmospheric pressure under an inert atmosphere. The reaction timegenerally depends on temperature, and generally is complete within 20hours, and preferably within 10 hours. An α-trihalomethyl-α-alkanol canbe utilized in place of a haloform and ketone, as noted hereinabove withregard to the trithiocarbonate compounds.

The O-alkyl-S-(α,α′-disubstituted-α″-acetic acid) xanthates can beutilized as an initiator to initiate or start the polymerization of amonomer, as a chain transfer agent which interrupts and terminates thegrowth of a polymer chain by formation of a new radical which can act asthe nucleus for forming a new polymer chain, and/or as a terminatorwhich are incorporated into a polymer as a dormant species. Preferably,the O-alkyl-S-(α,α′-disubstituted-α″-acetic acid) xanthates are utilizedas chain transfer agents in free radical polymerizations having livingcharacteristics to provide polymers of controlled molecular weight andlow polydispersity.

Xanthate (Co)Polymers

Polymers or copolymers of the following formulas can be prepared fromthe O-alkyl-S-(α,α′-disubstituted-α″-acetic acid) xanthates:

wherein a, R¹², R¹³, and R¹⁴ are as defined hereinabove, wherein thepolymer is derived from a conjugated diene monomer, or a vinylcontaining monomer, or combinations thereof, as defined hereinabove andincorporated by reference, and wherein each g repeat unit,independently, is the same or different and is generally from 1 to about10,000, and preferably from about 5 to about 500. Preferred monomers arealkyl acrylates, acrylic acid, and styrene. Of course, it is to beunderstood that when g is 1, the polymer is a single reacted monomerunit.

The above polymers or copolymers can be prepared by bringing intocontact with each other the monomer(s) which formO-alkyl-S-(α,α′-disubstituted-α″-acetic acid) xanthate compound, andoptionally a) solvent, and b) a radical polymerization initiator; insuitable amounts, as described hereinabove.

It is believed the mechanism is as follows:

As illustrated by the above mechanism, the monomers are polymerized intothe xanthate compounds adjacent to the thiocarbonylthio linkage, betweenthe single bonded sulfur atom and the tertiary carbon atom of thecompound.

The O-allyl dithiocarbonate compounds of the present invention can beused to produce polymers which are substantially colorless. The polymersor copolymers of the O-alkyl dithiocarbamate compounds are morehydrolytically stable because the electro-donating amino groups renderthe thiocarbonyl group less electrophilic and the polymers are stabletoward nucleophiles such as amines.

The reaction conditions are chosen as known to one skilled in the art sothat the temperature utilized will generate a radical in a controlledfashion, wherein the temperature is generally from about roomtemperature to about 200° C. The reaction can be performed attemperatures lower than room temperature, but it is impractical to doso. The temperature often depends on the initiator chosen for thereaction, for example, when AIBN is utilized, the temperature generallyis from about 40° C. to about 80° C., when azodicyanodivaleric acid isutilized, the temperature generally is from about 50° C. to about 90°C., when di-t-butylperoxide is utilized, the temperature generally isfrom about 110° C. to about 160° C., and whenO-alkyl-S-(α,α′-disubstituted-α″-acetic acid) xanthate is utilized, thetemperature is generally from about 80° C. to about 200° C.

As noted above with respect to the dithiocarbamate compounds, thepolymers or copolymers prepared from theO-alkyl-S-(α,α′-disubstituted-α″-acetic acid) xanthate contain reactiveend groups which are able to further undergo chemical transformation orreaction in order to be joined with another polymer chain, in order toform extended copolymers for example. The process of the invention canbe carried out, for example, in emulsion solution or suspension ineither a batch, semi-batch, continuous, bulk or feed mode.

Conventional procedures can be used to produce narrow polydispersitypolymers. For lowest polydispersity polymers, the chain transfer agentis added before polymerization is commenced. The polydispersity of thexanthate polymers or copolymers is generally less than about 3.0. Forexample, when carried out in batch mode in solution, the reactor istypically charged with chain transfer agent and monomer or medium plusmonomer. The desired amount of initiator is then added to the mixtureand the mixture is heated for a time which is dictated by the desiredconversion and molecular weight. Polymers with broad, yet controlled,polydispersity or with multimodal molecular weight distribution can beproduced by controlled addition of the chain transfer agent over thecourse of the polymerization process.

In the case of emulsion or suspension polymerization the medium willoften be predominately water and the conventional stabilizers,dispersants and other additives can be present. For solutionpolymerization, the reaction medium can be chosen from a wide range ofmedia to suit the monomer(s) being used.

As already stated, the use of feed polymerization conditions allows theuse of chain transfer agents with lower transfer constants and allowsthe synthesis of block polymers that are not readily achieved usingbatch polymerization processes. If the polymerization is carried out asa feed system the reaction can be carried out as follows. The reactor ischarged with the chosen medium, the chain transfer agent and optionallya portion of the monomer(s). The remaining monomer(s) is placed into aseparate vessel. Initiator is dissolved or suspended in the reactionmedium in another separate vessel. The medium in the reactor is heatedand stirred while the monomer+medium and initiator+medium are introducedover time, for example by a syringe pump or other pumping device. Therate and duration of feed is determined largely by the quantity ofsolution the desired monomer/chain transfer agent/initiator ratio andthe rate of the polymerization. When the feed is complete, heating canbe continued for an additional period.

Following completion of the polymerization, the polymer can be isolatedby stripping off the medium and unreacted monomer(s) or by precipitationwith a non-solvent. Alternatively, the polymer solution/emulsion can beused as such, if appropriate to its application. The applications forthe O-allyl-S-(α,α′-disubstituted-α″-acetic acid) xanthatedithiocarbonate compounds include any of those listed hereinabove withregard to the trithiocarbonate and dithiocarbamate compounds.

The dithiocarbonate compounds of the invention have wide applicabilityin the field of free radical polymerization and can be used asthickeners and to produce polymers and compositions for coatings,including clear coats and base coat finishes for paints for automobilesand other vehicles or industrial, architectural or maintenance finishesfor a wide variety of substrates. Such coatings can further includepigments, durability agents, corrosion and oxidation inhibitors,rheology control agents, metallic flakes and other additives. Block andstar, and branched polymers can be used as compatibilizers,thermoplastic elastomers, dispersing agents or rheology control agents.Additional applications for polymers of the invention are composites,potting resins, foams, laminate, in the fields of imaging, electronics(e.g., photoresists), engineering plastics, adhesives, sealants, papercoatings and treatments, textile coatings and treatments, inks andoverprint varnishes, and polymers in general, and the like.

The present invention will be better understood by reference to thefollowing examples which serve to describe, but not to limit, thepresent invention.

EXAMPLES Example 1 Synthesis of s,s′-bis-(α, α′-disubstituted-α″-aceticacid)-trithiocarbonate, (R¹=R²═CH₃)

Procedure:

In a 500 ml jacketed flask equipped with a mechanical stirrer, athermometer, a reflux condenser and an addition funnel added 22.9 gramsof carbon disulfide, 2.0 gram of tetrabutylammonium bisulfate and 100 mltoluene. The solution was stirred at 20° C. under nitrogen and 168 gramsof 50% sodium hydroxide solution was added dropwise to keep thetemperature between 20-30° C. 30 min. after the addition, a solution of43.6 grams of acetone and 89.6 grams of chloroform was added at 20-30°C. The reaction was then stirred at 15-20° C. overnight. 500 ml waterwas added to the mixture, the layers were separated. The organic layerwas discarded and the aqueous layer was acidified with concentrated HClto precipitate the product as yellow solid. 50 ml toluene was added tostir with the mixture. Filtered and rinsed the solid with toluene tocollect 22.5 grams of product after drying in the air to constantweight.

Example 2 Synthesis of s,s′-bis-(α, α′-disubstituted-α″-aceticacid)-trithiocarbonates. (R¹═R²=CH₃)

The procedure was essentially the same as in example 1, except thatmineral spirits replaced toluene as solvent. 40.3 grams of product wasobtained as yellow solid.

Example 3 Synthesis of s-alkyl-s′-(-(α, α′-disubstituted-α″-aceticacid)-trithiocarbonates

Procedure:

Dodecylmercaptan (0.1 mole), and Aliquot 336 (0.004 mole) was dissolvedin 48 g acetone. 50% sodium hydroxide solution (0.105 mole) was added,followed by dropwise addition of carbon disulfide (0-1 mole) in 10 gacetone solution. The media turned from colorless to yellow. After 20min., chloroform (0.15 mole) was added followed by dropwise addition of50% NaOH (0.5 mole) and 5 g NaOH beads. The r×n was stirred at 15-20° C.overnight, filtered and the sol. was rinsed with acetone. The acetonelayer was concentrated to dryness. The mass was dissolved in water,acidified with concentrated HCl to precipitate the product, rinsed withwater to collect the yellow solid. The solid was dissolved in 350 mlhexanes. The solution was dried over magnesium sulfate and filtered. Theorganic solution was cooled to precipitate the product as yellow flakes.Yield is 85%.

Example 4 Polymerization of Prior Art Compounds

Procedure:Dibenzyltrithiocarbonate (1.54 g, 5.3 mmole), 2-ethylhexylacrylate (25grams 135.7 mmole), AIBN (0.05 g, 0.3 mmole) and acetone (25 ml) weremixed.

1 ml of undecane was added as GC internal standard for calculating theconversion. The solution was purged with nitrogen for 15 min. beforeheating to 52° C. under nitrogen. No exotherm was detected throughoutthe reaction. Aliquots of the sample were taken for GC and GPA analysesduring the course of the polymerization. The following table showed theprogress of the polymerization in 7 hours. Sample Time (mins.) Mn MwConv. % 1 2 120 866 970 3.7 3 270 1180 1428 13.2 4 420 1614 2059 26.9

Example 5 Polymerization with s,s′-bis-(α, α′-disubstituted-α″-aceticacid)-trithiocarbonates

Procedure:

Following the same procedure as in example 4, the novel tricarbonate(1.50 g, 5.3 mmole), 2-ethylhexylacrylate (25 g, 135.7 mmole), AIBN(0.05 g, 0.3 mmole) and acetone (25 ml) were mixed. 1 ml of undecane wasadded as internal standard The reaction was stirred at 52° C. for 7hours. The following table showed the conversion and the molecularweights of the resulting polymer. Sample Time (mins.) Mn Mw Conv. % 1 45669 724 3.5 2 120 1433 1590 25.8 3 240 3095 3621 79.8 4 300 3345 389887.9 5 420 3527 4136 93.9

Example 6 Polymerization with s,s′-bis-(α, α′-disubstituted-α″-aceticacid) trithiocarbonates

Procedure:

This is a bulk polymerization with the trithiocarbonate aschain-transfer agent The trithiocarbonate (1.0 g, 3.5 mmole),2-ethylhexylacrylate (25 g, 135.7 mmole), AIBN (0.05 g, 0.3 mmole) and 1ml undecane (internal standard) were purged with nitrogen, then heatedto 60° C. for 3 hours. The following table showed the conversion and themolecular weight of the polymer. Sample Time (mins.) Mn Mw Conv. % 1 302229 2616 35.6 2 90 4501 5526 91.9 3 180 4672 5780 97.8

Example 7 Polymerization with s,s′-bis-(α, α″-disubstituted-α″-aceticacid) trithiocarbonates

Procedure:

The trithiocarbonate was used as inifertor. Trithiocarbonate (1.0 g, 3.5mmole), n-butylacrylate (20 g, 156.1 mmole) with 1 ml decane as internalstandard were purged with nitrogen for 15 min., then polymerized at 130°C. under nitrogen for 6 hours. The following table showed the conversionand the molecular weights of the polymer. Sample Time (mins.) Mn MwConv. % 1 60 1118 1242 16.0 2 120 1891 2199 32.5 3 240 2985 3337 52.5 4360 3532 4066 65.7

Example 8 Free Radical Polymerization utilizing s,s′-bis-(α,α″-disubstituted-α″-acetic acid)-trithiocarbonates as inifertor

Procedure:

The trithiocarbonate (2.0 g, 7.1 mmole) and 2-ethylhexylacrylate (25.0g, 135.7 mmole) were purged with nitrogen for 15 min then heated to 175°C. for 10 hours. The following table showed the conversion and molecularweighs of the polymer. Sample Time (mins.) Mn Mw Conversion 1 40 10061117 24.2 2 90 1446 1699 42.0 3 150 1750 2241 51.9 4 600 2185 3115 98.9

Example 9 Polymerization with s,s′-bis-(α, α″-disubstituted-α″-aceticacid) trithiocarbonates

Procedure:

The trithiocarbonate was used as inifertor to make polystyrene. Thetrithiocarbonate (2.0 g, 7.1 mmole) and styrene (25 g, 240.4 mmole) with1 ml decane as internal standard were polymerized at 140° C. undernitrogen for 6 hours. The following table showed the progress of thepolymerization. Sample Time (mins.) Mn Mw Conv. % 1 30 613 648 9.5 2 60779 831 16.9 3 120 1829 2071 53.9 4 300 2221 2559 72.3 5 360 2537 295684.5

Example 10 Polymerization with s,s′-bis-(α, α′-disubstituted-α″-aceticacid) trithiocarbonates

Procedure:

The trithiocarbonate was used as chain-transfer agent to make blockcopolymers of 2-ethylhexylacrylate and styrene. The trithiocarbonate(1.5 g, 5.3 mmole), 2-ethylhexylacrylate (30 g, 162.8 mmole) and AIBN(0.03 g, 0.18 mmole) with 1 ml undecane as the internal standard werepolymerized at 60° C. under nitrogen as before. 6.5 hours later, styrene(15 g, 144.2 mmole) and AIBN (0.03 g, 0.18 mmole) was added. Thepolymerization continued and the following shows the progress. SampleTime (mins.) Mn Mw Conv. % 1  70 1922 2459 32.5 2 135 3556 4204 80.8 3270 4095 4874 95.0 4  330* 4407 5025 96.6 5 1290  4834 5969 —*Styrene added

Example 11

Polymerization with the trithiocarbonate from example 3. Thetrithiocarbonate (1.82 g. 5 mmole), n-butyl acrylate (25 g, 195.1 mmole)and AIBN (0.04 g, 0.25 mmole) with 1 ml undecane as the internalstandard were polymerized under nitrogen atmosphere for 7 hours. Itshowed 97.5% conversion by GC as depicted in the following table: SampleTime (min) Mn Mw Pd % Conv. 1 60 2177 2792 1.26 46.2 2 120 2758 38651.40 67.1 3 420 3786 5439 1.44 97.5

Example 12

Procedure:

In a 300 ml jacketed flask equipped with a mechanical stirrer,thermometer, addition funnel and nitrogen-inlet tube (for inserting)16.3 grams potassium O-ethylxanthate, 17.9 grams chloroform, 1.36 gramstetrabutylammonium hydrogen sulfate and 88.1 grams cyclohexanone wereplaced and cooled to between 15-20° C. 40 grams of sodium hydroxidebeads were added in portions to keep the temperature below 25° C. Afterthe addition, the reaction was stirred at about 20° C. for 12 hours. 100ml of water was added and the aqueous layers were acidified withconcentrated hydrochloric acid. 100 ml toluene was added to extract theproduct. After drying the toluene solution with magnesium sulfate, itwas filtered and concentrated to afford 20 grams of yellow solid whichwas further purified by recrystallizing from hexanes.

Example 13

In this example, sodium O-ethylxanthate was formed in situ. 7.6 gramscarbon disulfide, 1 gram tetrabutylammonium hydrogen sulfate and 58.1grams acetone were stirred in a reaction vessel as equipped above inExample 12. 7.1 grams sodium ethoxide (96%, Aldrich) was added inportions at room temperature. 30 minutes after the addition, 17.9 gramschloroform was added followed by 20 grams sodium hydroxide beads inportions to keep the temperature below 25° C. Stirred at 15° C. for 12hours. The mixture was filtered and rinsed thoroughly with acetone. Theacetone solution was concentrated and dissolved in water. 20 mlconcentrated HCl was added. The oil formed was extracted into two 50 mlportions of toluene, dried over magnesium sulfate, and concentrated intoan oil. The oil was extracted with two 50 ml portions of boiling hexane.Beige-colored solid was produced from the solution.

Example 14 Synthesis of S-(methyl, methyl, acetic acid) dithiocarbamate

Procedure:

10.7 grams sodium N,N-diphenyldithiocarbamate, 7.2 grams chloroform, 4.6grams acetone, 0.8 gram Aliquot 336 and 50 ml toluene were stirred at15-20° C. under nitrogen while 16 grams 50% sodium hydroxide was addeddropwise to keep the reaction temperature below 20° C. The reaction wasstirred for 12 hours. Water was added to dissolve the solid. The layerswere separated and the aqueous layer was acidified with concentratedhydrochloric acid. The solid was washed with water and recrystallizedfrom toluene to afford light-yellow colored solid.

Example 15

Procedure:

Sodium N,N-diphenyldithiocarbamate was replaced by sodiumN,N-hexamethylenedithiocarbamate and the reaction was conducted asexplained in Example 14. The product was a white solid.

Example 16

Procedure:

The sodium dithiocarbamate utilized in this example was sodiummorpholinodithiocarbamate. The reaction was conducted as explained inExample 14. The product was afforded in good yield as white powders.

Example 17

Procedure:

The sodium dithiocarbamate utilized in this example was sodiumN,N-diethyl dithiocarbamate. The reaction was conducted as explained inExample 14 and acetone was replaced by cyclohexanone. The product wasafforded in good yield as white powders.

Example 18

Procedure:

Sodium N,N-dibutyldithiocarbamate was utilized in this example.

The reaction was conducted as described in Example 14. The product wasisolated as white powder.

Example 19

Procedure:

Sodium N,N-di-isobutyidithiocarbamate was utilized in this example. Thereaction was conducted as described in Example 14. The product wasisolated as yellow solid.

Example 20

Procedure:

Sodium N,N-hexamethylene dithiocarbamate, 2-butanone was utilized inthis example. The reaction was conducted as explained in Example 14 andwas replaced by acetone. The product was afforded in good yield as whitepowder after recrystallization from hexane/toluene.

Example 21

Procedure:

14.1 grams of S,S′-disodium salt of the piperazine bis-(dithiocarbamicacid), 100 ml 2-butanone, 17.9 grams chloroform and 1.13 gramsbenzyltriethylammonium chloride were mixed and stirred at 15-20° C.under nitrogen atmosphere. 40 grams 50% sodium hydroxide solution wasadded in portions to keep the reaction temperature under 20° C. Afterthe addition, the reaction was allowed to stir at 20° C. for 12 hours.The mixture was filtered and the solid was rinsed with 2-butanone andthen stirred with 100 ml water. Concentrated HCl was added until waterturned acidic. The solid was collected and rinsed with water, to yieldoff-white colored powders. The powder was crystallized with methanol toafford white powder.

Example 22

As in the above procedure of Example 21 the disodium salt of piperizinebis-(dithiocarbamic acid) was replaced with sodiumdiethyldithiocarbamate, and 2-butanone with acetone. The desired productwas obtained as white powders in high yield.

Example 23

The procedure of Example 21 was utilized and the disodium salts ofpiperizine bis-(dithiocarbamic acid) was replaced by sodiumdimethyldithiocarbamate, and BTEAC was replaced by tetrabutylammoniumhydrogensulfate, the desired product was obtained as white powders.

Example 24

The reaction was performed as in Example 21, but the dithiocarbamatesalt was sodium N-phenyl-N-1-naphthyl dithiocarbamate, and the ketonewas acetone. The product was obtained as beige-colored powders afterrecrystallization from a mixture of toluene and heptane.

Example 25

The reaction was performed in a similar manner as in Example 21, but2-butanone was replaced by 2-pentanone, the product was white powdersafter recrystallization from hexanes.

Example 26

Procedure:

7.38 grams diethylamine and 80 ml acetone and 2.0 grams Aliquot 336 weremixed and stirred under nitrogen atmosphere at 15° C. 7.6 grams carbondisulfide in 20 ml acetone was added dropwise to keep the temperaturebelow 20° C. 30 minutes after the addition, 8.8 grams 50% sodiumhydroxide was added. 30 minutes later, 17.9 grams chloroform was addedfollowed by 31.2 grams 50% sodium hydroxide. The reaction was allowed tostir at 15-20° C. for 12 hours. The mixture was concentrated and thendissolved in water. 15 ml concentrated HCl was added to precipitate abeige-colored solid which was washed thoroughly with water (20 grams).Recrystallization from toluene afforded white solid.

Example 27

Procedure:

The diethylamine of the procedure of Example 26 was replaced byhexamethyleneimine and acetone was replaced by methyl isobutyl ketone.The product was recrystallized from hexane/toluene to afford whitepowders.

Example 28

The diethylamine of the procedure of Example 26 was replaced bydialkylamine and Aliquot® 336 was replaced by BTEAC. The product waswhite crystalline solid after recrystallization from hexane/toluene.

Example 29

The diethylamine of the procedure of Example 26 was replaced bydimethyl-amine (40% in water). The product was white crystals afterrecrystallization from toluene.

Example 30

The acetone of the procedure of Example 27 was replaced by 2-butanone.The produce was a white solid after recrystallization from toluene.

Example 31

The acetone of the procedure of Example 26 was replaced bycyclohexanone. The product was white solid after recrystallization fromtoluene.

Example 32

In this example, 22.8 grams of sodium N-phenyl-N-4-anlinophenyldithiocarbamate, 17.9 grams chloroform and 100 ml acetone were mixed andstirred at 15° C. under nitrogen. 40 grams 50% sodium hydroxide wasadded dropwise in to keep the temperature under 20° C. The reaction wasallowed to stir overnight (approximately 12 hours) at 15° C. Solvent wasremoved in a rotary evaporator and the residue was dissolved in water.The aqueous solution was acidified with concentrated hydrochloric acidto collect a green-colored solid. The dried solid was recrystallizedfrom toluene to afford grayish-colored solid. The structure wasconfirmed by H-NMR.

Example 33 Controlled Radical Polymerization with Novel DithiocarbonateDerivatives

The theoretical number-averaged molecular (Mn)_(theo) weight for eachpolymer or copolymer was calculated from the formula XII (a) assuming100% conversion.

(Mn)_(ex) is the Mn measured by GPC from polymerization products. Inbulk polymerization, 20-25 grams of monomer, 0.01-0.05 grams of aninitiator such as AIBN and the amount of the dithiocarbonate as neededto give desired Mn (calculated using formula XII(a)) are purged withnitrogen gas, then heated to temperature gradually. Sometimes air orwater-cooling is necessary to keep the temperature under 83° C. Theresulting polymers were subjected to MALDI mass spectrum measurement.The spectrum clearly showed the carboxyl-terminating group in everypolymer chain.

Block copolymerization was performed by making the first polymer inbulk, then add the second monomer and same amount of initiator, thenpolymerizing in the same manner. Random copolymerization could have beenperformed if both monomers were added at the same time.

The results of the polymerizations and block polymerizations are listedin the following table. Dithiocarbonate Polymers Dithiocarbonate Time/Example Monomer Solvent Temp. (Mn)_(ex) (Mn)_(theo) PD Hour ControlButyl acrylate — >100,000 >3 1 12 Butyl acrylate MEK 80 3777 5000 1.78 526 Styrene none-bulk polym. 140 7830 5000 2.05 5 17 Butyl acrylate MEK80 1645 2000 2.07 5 14 Butyl acrylate MEK 75 4656 5000 1.31 5 21 Butylacrylate MEK 80 3049 3000 1.32 6 19 Butyl acrylate MEK 80 3683 3000 2.036 13 Ethyl acrylate none-bulk polym. 65 5564 10000 1.83 5 29 Vinylacetate none-bulk polym. 70 4367 5000 1.47 5 15 t-butylacrylamide THF 703622 5000 1.91 5 24 Butyl acrylate none-bulk polym. 80 5093 5000 1.366.5 32 Butyl acrylate MEK 80 2061 5000 1.61 2.5 Block CopolymersDithiocarbonate Example Monomer-1 (Mn)_(ex) (Mn)_(theo) PD Monomer-2(Mn)_(ex) (Mn)_(theo) PD 30 Butyl acrylate 1695 1798 1.92 Vinyl acetate1873 2540 1.87 31 Butyl acrylate 1631 1798 2.23 Vinyl acetate 2014 24441.96

While in accordance with the patent statutes the best mode and preferredembodiment have been set forth, the scope of the invention is notlimited thereto, but rather by the scope of the attached claims.

1-52. (canceled)
 53. A method for forming aO-alkyl-S-(α,α′-disubstituted-α″ acetic acid) xanthate compound,comprising the steps of: reacting a alkoxylate salt of a xanthatecompound, carbon disulfide, a haloform, and a ketone in the presence ofa base, and optionally a solvent and a catalyst, to form a reactionproduct; and acidifying said reaction product to form saidO-alkyl-S-(α,α′-disubstituted-α″ acetic acid) xanthate compound.
 54. Amethod according to claim 53, wherein said reaction is conducted at atemperature from about minus 15° C. to about 80° C.
 55. A methodaccording to claim 54, wherein said haloform is chloroform or bromoform,or a blend thereof, and wherein said ketone has the formula:

wherein R¹² and R¹³, independently, can be the same or different, canoptionally be substituted, and can be a linear or branched alkyl havingfrom 1 to about 12 carbon atoms; or an aryl group having from 6 to about18 carbon atoms, optionally containing heteroatoms; or R¹² and R¹³ canform and be part of a substituted or unsubstituted cyclic ring havingfrom 3 to about 12 carbon atoms.
 56. A method according to claim 55,including said catalyst.
 57. A method according to claim 55, whereinsaid O-alkyl-S-(α,α′-disubstituted-α″ acetic acid) xanthate compound hasa formula:

wherein R¹⁴ is optionally substituted, and can be a linear or branchedallyl having from 1 to about 12 carbon atoms, an aryl group optionallysaturated or unsaturated; an arylalkyl having from about 7 to about 18carbon atoms; an acyl group; an alkene group; an alkenealkyl having from3 to about 18 carbon atoms; an alkylene group; an alkoxyalkyl; derivedfrom a polyalkylene glycol; derived from a polyalkylene glycol monoalkylether having from about 3 to about 200 carbon atoms; derived from apolyalkylene glycol monoaryl ether having from about 3 to about 200carbon atoms, a polyfluoroalkyl; a phosphorous containing alkyl; or asubstituted or unsubstituted aryl ring containing heteroatoms; andwherein said “a” is 1 to about
 4. 58. A method according to claim 57,wherein said haloform is utilized in an amount from 0 percent to about500 percent molar excess and said ketone is used in an amount from 0percent to about 300 percent molar excess, based on the molar amount ofsaid metal salt of said dithiocarbamate.
 59. A method according to claim58, wherein R¹² and R¹³, independently, are a phenyl group or an alkylgroup having 1 to about 10 carbon atoms, or wherein R¹² and R¹³ are partof a cyclic ring, and wherein R¹⁴ is an allyl having from 1 to about 8carbon atoms.
 60. A method for forming anO-alkyl-S-(α,α′-disubstituted-α″ acetic acid) xanthate polymer orcopolymer, comprising the steps of: providing aO-alkyl-S-(α,α′-disubstituted-α″-acetic acid) xanthate compound havingthe formula:

wherein R¹² and R¹³, independently, can be the same or different, can bea linear or branched alkyl having from 1 to about 12 carbon atoms; or anaryl group having from 6 to about 18 carbon atoms, optionally containingheteroatoms; or R¹² and R¹³ can form or be a part of a substituted orunsubstituted cyclic ring having from 3 to about 12 carbon atoms;wherein R¹⁴ is optionally substituted, and can be a linear or branchedallyl having from 1 to about 12 carbon atoms, an aryl group optionallysaturated or unsaturated; an arylalkyl having from about 7 to about 18carbon atoms; an acyl group; an alkene group; an alkenealkyl having from3 to about 18 carbon atoms; an alkylene group; an alkoxyalkyl; derivedfrom a polyalkylene glycol; derived from a polyalkylene glycol monoalkylether having from about 3 to about 200 carbon atoms; derived from apolyalkylene glycol monoaryl ether having from about 3 to about 200carbon atoms, a polyfluoroalkyl; a phosphorous containing alkyl; or asubstituted or unsubstituted aryl ring containing heteroatoms; whereinsaid “j” is 1 to about 4; and reacting at least one vinyl-containingmonomer, or at least one conjugated diene monomer with saidO-alkyl-S-(α,α′-disubstituted-α″-acetic acid) xanthate compound.
 61. Amethod according to claim 60, wherein said conjugated diene monomer hasfrom 4 to 12 carbon atoms, and wherein said vinyl containing monomer hasthe formula:

wherein R³ comprises hydrogen, halogen, C₁-C₄ alkyl, or substitutedC₁-C₄ alkyl wherein said substituents, independently, comprise one ormore hydroxy, alkoxy, aryloxy(OR⁵), carboxy, acyloxy, aroyloxy(O₂CR⁵),alkoxy-carbonyl(CO₂R⁵), or aryloxy-carbonyl; N-pyrrolidonyl; wherein R⁴comprises hydrogen, R⁵, CO₂H, CO₂R⁵, COR⁵, CN, CONH₂, CONHR⁵, O₂CR⁵, OR⁵or halogen; and wherein R⁵ comprises C₁-C₁₈ alkyl, substituted C₁-C₁₈alkyl, C₂-C₁₈ alkenyl, aryl, heterocyclyl, aralkyl, or alkaryl, andwherein said substituents, independently, comprise one or more epoxy,hydroxy, alkoxy, acyl, acyloxy, carboxy, (and salts), sulfonic acid (andsalts), alkoxy- or aryloxy-carbonyl, dicyanato, cyano, silyl, halo ordialkylamino.
 62. A method according to claim 61, wherein saidvinyl-containing monomer is derived from alkyl acrylate, vinyl acetate,acrylic acid, styrene, or N-vinyl pyrrolidone or a combination thereof.63. A method according to claim 62, wherein R¹² and R¹³, independently,are a phenyl group or an alkyl group having 1 to about 10 carbon atoms,or wherein R¹² and R¹³ are part of a cyclic ring.
 64. A method accordingto claim 63, wherein j is 2, and wherein R¹² and R¹³, independently, area phenyl group or alkyl group having 1 to about 10 carbon atoms, or R¹²and R¹³ are part of a cyclic ring, and wherein R¹⁴ is an alkyl havingfrom 1 to about 8 carbon atoms.